1. Field of the Invention
The invention pertains generally to compact disc drive mechanisms, and more particularly to a support structure for a spindle motor of a compact disc machine.
2. Description of the Background Art
The conventional support structure for a spindle motor of a compact disc machine typically consist of a spindle motor assembly having a rotor base, a shaft and a support plate. A circular hub is mounted over the spindle motor and receives the axial hole of a compact disc. It is conventional practice to utilize a metal plate press to bind the rotor base, the shaft and the support plate together. However, such a binding method is incapable of achieving a high degree of precision. Additionally, the assembled spindle motor often fails to meet baseline standards.
After a period of usage, loosening and separation among the components occur, and thus, reliability of the spindle motor and support structure becomes a problem. Additionally, during the manufacturing process of the spindle motor, the shaft, which must be positioned perpendicular relative to the support plate, has a tendency to incline off a perpendicular orientation relative to the support plate. An inclined shaft causes an eccentric vibration of the rotor base and results in inducing vibration throughout the entire support structure of the spindle motor. Such vibration accentuates the loosening and separation among the components.
A problem also exists with the circular hub, which serves the function of maintaining the compact disc concentrically over the support structure and securing the disc thereon. The circular hub typically has metallic spheres disposed circumferentially at evenly spaced intervals around the circular hub for locking the hole of a disc securely on the support structure. In order, however, for the metallic spheres to engage and lock the compact disc, each metallic sphere must provide some degree of elasticity or resiliency. This elasticity or resiliency is accomplished with a rubber ring inserted within the circular hub to resist and absorb movements inward radial movement of the metallic spheres as the hole of the compact disc engages the circular hub. This rubber ring, however, detaches very easily such that the metallic spheres lose their elastic capability, thereby destroying one of the hub's functions.
Thus, there exist a need for a spindle motor support structure that is capable precisely and reliably binding the shaft, rotor base and support plate together, as well as to reliably engage and secure a compact disc on the support structure. The present invention satisfies these needs, as well as others, and generally overcomes the deficiencies presently known to exist.